208000181 has 2 divisors, whose sum is σ = 208000182. Its totient is φ = 208000180.

The previous prime is 208000139. The next prime is 208000183. The reversal of 208000181 is 181000802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 206640625 + 1359556 = 14375^2 + 1166^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-208000181 is a prime.

It is a super-2 number, since 2×208000181² = 86528150592065522, which contains 22 as substring.

Together with 208000183, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (208000183) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104000090 + 104000091.

It is an arithmetic number, because the mean of its divisors is an integer number (104000091).

Almost surely, 2^208000181 is an apocalyptic number.

It is an amenable number.

208000181 is a deficient number, since it is larger than the sum of its proper divisors (1).

208000181 is an equidigital number, since it uses as much as digits as its factorization.

208000181 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128, while the sum is 20.

The square root of 208000181 is about 14422.2113769006. The cubic root of 208000181 is about 592.4993855442.

Adding to 208000181 its reverse (181000802), we get a palindrome (389000983).

The spelling of 208000181 in words is "two hundred eight million, one hundred eighty-one", and thus it is an aban number.